Australian Flora Foundation FINAL REPORT

Presentation on theme: "Australian Flora Foundation FINAL REPORT"— Presentation transcript:

1 Australian Flora Foundation FINAL REPORT
Life histories and reproductive strategies of halophytic plants: suitability of Frankenia (Frankeniaceae) for revegetation in Australia. Prepared by: Dr Lyndlee C. Easton School of Biological Sciences Flinders University GPO Box 2100, Adelaide 5001 25th June 2008

2 Project summary This PhD project provided information on the life histories and reproductive strategies of Australian plant species in the genus Frankenia. Global distribution Mediterranean coastal, and arid inland regions Specialised soil types e.g. saline and gypseous soils Australia has the greatest number of species of Frankenia

3 Project summary Small shrubs, sub-shrubs or herbs, Habitats: coastal cliffs, sand dunes, coastal salt marshes, margins of salt lakes and salt pans.

4 Project summary Frankenia were investigated because they occur naturally in harsh environments (1) Use in revegetation projects - coastal zones or salt affected regions (2) Plant cultivation - tolerance to saline and drought conditions.

5 Project summary This project provided key data on interspecific variation in reproductive strategies Variation in seed mass/number per fruit Significance on germination success under different environmental conditions Ambient temperature Salinity levels Soil properties Seed mineral content

6 Project Aims Two primary aims: To examine germination across Frankenia for seed age, light requirements, temperature preferences, salinity tolerance, and soil characteristics at the seed and seedling stage Practical significance - halophytic and saltmarsh plants (e.g. Frankenia) play a major role in reclamation programs associated with increasing salinity problems, and/or mine-site revegetation.

7 Project aims 2. To examine variation in seed mass and number among species of Frankenia to test hypotheses concerning the consequences of these variations for seedling establishment under different ambient conditions. Practical significance - produced basic information on the reproductive biology of Frankenia, including some that are of conservation significance several species have limited or disjunct distributions or are little known e.g. F. plicata is of particular conservation significance in South Australia

8 Project Results. Project Aims
Investigate germination requirements for Frankenia in relation to seed age, light requirements, temperature preferences, salinity tolerance, and soil characteristics. Investigate two divergent reproductive strategies – notably seed packaging strategies – in relation to environmental variables. Project Results.

9 Project Aims Investigate germination requirements for Frankenia in relation to seed age, light requirements, temperature preferences, salinity tolerance, and soil characteristics. Investigate two divergent reproductive strategies – notably seed packaging strategies – in relation to environmental variables. Project results Overall, larger-seeded Frankenia species were demonstrated to be advantageous for rapid germination after transitory water availability, and for providing resources to seedlings if resources became limiting before their successful establishment.

10 Project Aims Investigate germination requirements for Frankenia in relation to seed age, light requirements, temperature preferences, salinity tolerance, and soil characteristics. Investigate two divergent reproductive strategies – notably seed packaging strategies – in relation to environmental variables. Project results Overall, larger-seeded Frankenia species were demonstrated to be advantageous for rapid germination after transitory water availability, and for providing resources to seedlings if resources became limiting before their successful establishment. Smaller-seeded species delayed germination until both soil-water availability and cooler temperatures persisted over a longer time period, improving chances of successful establishment for the more slowly growing seedlings that are more reliant on their surroundings for resources

11 The results of each facet of this project was documented as chapters of my PhD thesis entitled:
Easton, L.C. (2008) ‘Life history strategies of Australian species of the halophyte and arid zone genus Frankenia L. (Frankeniaece)’. Flinders University, Adelaide, Australia. Each chapter was written as a manuscript for publication in peer review journals. The publication status of each manuscript is included in the manuscript abstract.

12 For the results of salinity levels and seed mass on germination in Australian Frankenia species, please refer to manuscript ‘A’. Easton, L.C. & Kleindorfer, S. (2009) Effects of salinity levels and seed mass on germination in Australian species of Frankenia l. (Frankeniaceae). Experimental and Environmental Botany. 65: Figure 1. Germination rates, calculated using a modified Timson Index at Days, 2, 3, 6, and 8 at salinity levels of 0%, 10%, 20%, and 30%. Germination rates (a) comprises F. cinerea, F. cordata and F. fecunda. Germination rates (b) comprises F. foliosa, F. interioris and F. laxiflora. Germination rates (c) comprises F. pauciflora var. gunnii (SA varieties), F. pauciflora var. pauciflora (WA varieties) and F. serpyllifolia. Germination rates (d) comprises F. sessilis, F. setosa and F. tetrapetala.

13 2. For soil characteristics associated with the habitats of central and southern Australian Frankenia species, please refer to manuscript ‘B’. Easton, L. C. & Kleindorfer, S. (in review) Soil characteristics associated with the habitats of central and southern Australian Frankenia L. species (Frankeniaceae). Plant and Soil. Figure 3. Scatterplot generated by the first 2 Discriminant Function scores calculated to identify soil characteristics that maximise the differences between the 41 Frankenia populations included in this study. Open circles represent larger-seeded species. Closed triangles represent smaller-seeded species. Label numbers represent species as follows: (1) F. connata, (2) F. cordata, (3) F. eremophila, (4) F. foliosa, (5) F. gracilis, (6) F. latior, (7) F. pauciflora var. fruticulosa, (8) F. pauciflora var. gunnii, (9) F. planifolia, (10) F. plicata, (11) F. serpyllifolia, (12) F. sessilis, (13) F. subteres.

14 3. For the germination requirements for individual Australian species of Frankenia, please refer to manuscript ‘C’. Easton, L.C. & Kleindorfer, S. (in review) Germination requirements for Australian species of Frankenia L. (Frankeniaceae). Figure 1. Germination rates for Frankenia species, as calculated by a modified Timson Index, by Day 8. Abbreviations are as follows; ‘cin’ F. cinerea, ‘con’ F. confusa, ‘fec’ F. fecunda, ‘fol’ F. foliosa, ‘lax’ F. laxiflora, ‘mag’ F. magnifica, ‘p(SA)’ F. pauciflora var. fruticulosa, ‘p(WA)’ F. pauciflora var. pauciflora, ‘cor’ F. cordata, ‘ere’ F. eremophila, ‘grac’ F. gracilis, ‘int’ F. interiores, ‘plan’ F. planifolia, ‘serp’ F. serpyllifolia, ‘ses’ F. sessilis, ‘set’ F. setosa, ‘tet’ F. tetrapetala. Grey shading represents smaller-seeded species. Black shading represents larger-seeded species

15 4. For seed mineral nutrient contents of Australian species of Frankenia, please refer to manuscript ‘D’. Easton, L.C. & Kleindorfer, S. (in prep). Seed mineral nutrient contents in Australian species of Frankenia L. (Frankeniaceae). Plant Sciences. Figure 1. Scatterplot generated by the first 2 Discriminant Function scores calculated to identify the seed mineral nutrient content interactions that maximise the differences between Frankenia populations included in this study. Solid circles are larger-seeded species. Open triangles are smaller-seeded species. Label numbers represent species as follows: (1) F. cinerea, (2) F. cordata, (3) F. eremophila, (4) F. fecunda, (5) F. foliosa, (6) F. glomerata, (7) F. gracilis, (8) F. interioris, (9) F. irregularis, (10) F. laxiflora, (11) F. magnifica, (12) F. pauciflora var. gunnii, (13) F. pauciflora var. pauciflora, (14) F. planifolia, (15) F. serpyllifolia, (16) F. sessilis, (17) F. subteres, (18) F. tetrapetala.

16 5. For the results of the interaction effects of seed mass and temperature on Australian species of Frankenia, please refer to manuscript ‘E’. Easton, L.C. & Kleindorfer, S. (2008) Interaction effects of seed mass and temperature on germination in Australian species of Frankenia L. (Frankeniaceae). Folia Geobotanica. 43: Figure 2. Partial Eta Square values for each 2-day time interval showing the proportion of the germination rates accounted for by the interaction of seed mass and species at 17°C, 23°C, and 29°C.

17 6. For the effects of seed mass, seed age, light and temperature on Frankenia serpyllifolia and F. foliosa, please refer to manuscript. Easton, L.C. & Kleindorfer, S. (2008) Germination in two Australian species of Frankenia L., F. serpyllifolia Lindl. and F. foliosa J.M.Black (Frankeniaceae) – effects of seed mass, seed age, light, and temperature. Transactions of the Royal Society of South Australia 132(1): Fig. 3. Germination success for F. serpyllifolia (larger-seeded species) and F. foliosa (smaller-seeded species) after 21 days for seed age categories 1-, 7-, and 20-years.

18 Thank you